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EuSpRIG - Dr Simon Thorne

@eusprig.bsky.social

110 followers 300 following 190 posts

Programme chair for The European Spreadsheet Risks Interest Group, EuSpRIG - (“yewsprig”) for short. Academic and researcher in software and spreadsheet quality

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 30

Can't physically come to EuSpRIG 2025? We now have streaming tickets available for a reduced rate: eventbrite.co.uk/e/eusprig-20...

@standupmaths.bsky.social @cst.cam.ac.uk @msftresearch.bsky.social @ucl.ac.uk @cardiffmet.bsky.social @cipfa.bsky.social
@icaew.bsky.social @davidcolver.bsky.social

EuSpRIG 2025 Annual Conference: Spreadsheet Productivity and Risks

Join us at EuSpRIG 2025 for insights on boosting your spreadsheet skills while managing risks - it's gonna be epic!

eventbrite.co.uk

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

7. MI5's bug the wrong people
MI5 collected the wrong phone data 1,061 times
Why? A formatting error in Excel requested numbers ending in “000”
#YouOnlyFormatTwice

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

6. Excel audit trail catches fraudster
A Harvard Prof. falsified data in behavioural studies.
It was Excel’s audit trail that exposed her.
Sometimes spreadsheets fight back.
#Integrity #Audit

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

5. The gene name tragedy
Scientists keep naming genes things like “MARCH1”
Excel helpfully turns them into dates.
20 years on, the problem still breaks research papers.
#Bioinformatics #ExcelFails

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

4. Courtroom chaos
During the Proud Boys trial, prosecutors accidentally shared classified messages.
They’d filtered them out — but they remained in hidden rows.
Discovered live in court.
#LegalFail #FOI

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

3. $92M on the line
Norway’s $1.5 trillion sovereign fund lost $92M.
All because someone entered the wrong date in a benchmark spreadsheet. One cell. Nine figures.
#FinanceRisk #Excel

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

2. Active MI5 staff compromised
Police in Northern Ireland accidentally published personal data of 10,799 staff, incl. MI5 operatives.
A hidden tab in Excel. A massive breach.
Cost: £200m+.
#DataRisk #SpreadsheetFail

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

1. Avoidable deaths
Public Health England lost 16,000 COVID test results
Why? They used an outdated Excel file format with a row limit. 1,500 avoidable deaths.
#EuSpRIG2025
www.eventbrite.co.uk/e/eusprig-20...

EuSpRIG 2025 Annual Conference: Spreadsheet Productivity and Risks

Join us at EuSpRIG 2025 for insights on boosting your spreadsheet skills while managing risks - it's gonna be epic!

www.eventbrite.co.uk

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 19

Why you should care about spreadsheet risk – and come to #EuSpRIG2025

Every year, billions depend on spreadsheets. And every year, they go horribly wrong.

Here are 7 real cases that prove why #ExcelFails matter.👇

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 13

Out of interest, would a day workshop run by EuSpRIG on the safe use of #LLMs/#GenerativeAI for #spreadsheet modelling be of interest to people? We could do an in person or online workshop

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 13

Join our new EuSpRIG page on Linkedin!

www.linkedin.com/company/eusp...

The European Spreadsheets Risks Interest Group (EuSpRIG) | LinkedIn

The European Spreadsheets Risks Interest Group (EuSpRIG) | 31 followers on LinkedIn. The European Spreadsheet Productivity & Risks Interest Group – EuSPRIG – (“yewsprig”) for short | The European ...

www.linkedin.com

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 11

Excited about my new paper: Large Language Models for #Spreadsheets introduces the #FLARE #benchmark, a deep dive into how #LLMs handle real spreadsheet logic, symbolic reasoning and error detection.
They sound confident, but still make dangerous mistakes. www.eventbrite.co.uk/e/eusprig-20...

EuSpRIG 2025 Annual Conference: Spreadsheet Productivity and Risks

Join us at EuSpRIG 2025 for insights on boosting your spreadsheet skills while managing risks - it's gonna be epic!

www.eventbrite.co.uk

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 10

"The Devil's guide to Vibe Driven Development" A chaotic, hilarious manifesto for anyone who's ever coded by gut feeling and vibes alone. You’ve done agile. Now try unhinged. Be careful with #LLMs and always validate and verify

recondite-basket-7d0.notion.site/The-Devil-s-...

The Devil's Guide to Vibe-Driven Development 👹 | Notion

1. Just Code by Vibes 🎯

recondite-basket-7d0.notion.site

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 6

decision makers using these spreadsheets second hand did not realise that the data may be limited or the assumptions too narrow for general purpose. All of this could have been avoided with a better system to analyse the results in the first place.

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 6

scientists were not able to run ad-hoc queries on the database containing results, so the data was exported to Excel for analysis (sounds familiar), what was not realised was that these spreadsheets were for very specific purposes with specific assumptions...

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · Jun 6

An #Excel formula error led to inaccuracies in 69 test results across 37 paternity and kinship cases, spanning from 1982 to 2023. However, this is probably not an "error" in the traditional sense, the report details that...

www.nationaltribune.com.au/labor-s-dna-...

Labor’s DNA Debacle deepens with kinship and paternity errors uncovered

Labor’s DNA Debacle deepens with kinship and paternity errors uncovered Forensic Science Queensland has halted all kinship and paternity testing after

www.nationaltribune.com.au

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 30

EuSpRIG 2025 Annual Conference: Spreadsheet Productivity and Risks

Join us at EuSpRIG 2025 for insights on boosting your spreadsheet skills while managing risks - it's gonna be epic!

eventbrite.co.uk

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

AI could be as transformative to audit as the spreadsheet was to accounting. But this will only happen if firms integrate it with care—balancing automation with accountability, and innovation with ethics.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

EY, Accenture, Grant Thornton and others are investing heavily, partnering with major tech providers like Microsoft, Nvidia, and Google to embed AI across audit services. Falling behind could mean lower quality outcomes and reduced competitiveness.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

Ethical deployment of AI requires:
– Transparent algorithms
– Bias audits and explainability
– Consistent data quality standards
– Clear escalation protocols
Without these, AI’s credibility in audit work is at risk

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

AI trained on past fraud may fail to detect new, creative fraud techniques. Over-reliance can dull professional skepticism. Leading firms stress the importance of human oversight and contextual understanding.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

AI models can absorb historical biases—especially if the training data includes discriminatory decisions. For example, some LLM-based tools have shown racial bias in mortgage approvals. Auditing tools face similar risks of embedding flawed assumptions.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

AI enables full-population testing, not just samples. It can detect subtle patterns, suggest strategic insights, and even scan past engagements to strengthen pitches and planning.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

Thomson Reuters beta testers reported halved sample sizes and faster audit testing. Deloitte suggests AI could reduce audit costs by 25% through automation of routine work.

EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

EY trialled an AI fraud-detection tool with 10 UK clients. It flagged issues in two cases—both later confirmed as fraud. That's a strong signal that AI can detect what human sampling might miss.

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EuSpRIG - Dr Simon Thorne @eusprig.bsky.social · May 16

Recent audit failures have exposed the limits of traditional methods. Auditors need tools that can detect anomalies across entire datasets. AI is stepping into that role. Although my own testing suggests that this is still quite limited - check my forthcoming 2025 EuSpRIG paper